A High Performance Digital Ionosonde System

The ionosonde is a familiar instrument in radio science, with hundreds of systems around the world providing a near-continuous characterization of ionosphere configuration and dynamics. For DoD, the ionosonde is a crucial logistical asset, particularlyfor operational communications prediction. However, the majority of current ionosonde instruments suffer from hardware and operational shortcomings that limit their quality of their data, and hence the accuracy of the characterizations. Recently, it hasbeen shown that some of these errors can be resolved by reinterpretation the data, but often the hardware limits the effectiveness, in terms of both cost and success, of this approach.A high frequency radar design is near completion that addresses the key hardware weaknesses of the current ionosonde designs. The gain in performance comes from the convergence of high-speed digital tools and techniques that are used in a fully digitaldesign of the low power portions of the system. Digital detection allows full utilization of the signal returns, as well as providing solutions to the spectral issues that normally limit ionosonde performance. An added advantage is that the low-powerhardware can be replicated at a fraction of the cost of an analog transceiver with similar performance.